We have all heard many statements, as children and as adults, that give advice on what to do if a tornado threatens. Some of these statements have withstood scientific scrutiny, and are considered tornado facts. But evidence has shown that some are just tornado myths. How can you know which is which? Read on!

The first myth commonly heard is “Open windows to equalize pressure.” This is a very dangerous tornado myth for two reasons – it is best to stay away from windows which are likely to produce flying shards of glass, and open windows allow outside debris to enter the home. Opening the windows does not prevent building collapse due to pressure changes and high winds. In fact, if the tornado is close, time is critical, and the time spent opening windows could mean the difference between life and death.

Don’t stop to open windows if a tornado is imminent! Go immediately to a basement or inner room/hallway, get under a heavy piece of furniture if possible, and protect your head and neck with a pillow or mattress. If a tornado warning has been issued, but the tornado has not reached your area, close blinds and/or curtains for some protection against flying glass and debris.

The second tornado myth is that the southwestern corner of a basement is the safest place to be in a tornado. This myth was based on the belief that debris would concentrate in the northeast corner, since most tornadoes move in that direction. However, research has shown that the southwest corner is often the most dangerous place. Many tornadoes are strong enough to move the foundation of a house, and their full force will hit the southwest corner, possibly collapsing the basement walls on top of anyone in that area. The safest place to be in a tornado – if you do not have an underground tornado shelter -- is the middle of the basement under heavy furniture such as a worktable, or in an interior, windowless room or hallway on the first floor.

Another dangerous tornado myth is “Overpasses are safe haven for cars during a tornado.” Again, the exact opposite is true. An overpass may keep the rain off your car, but it offers little protection from flying debris. Also, stopping under an overpass during a storm, especially when the rain is heavy, may result in a crash if other drivers cannot see you. If you are driving and a tornado is near, take shelter in a sturdy building if one is available. Otherwise, stop the car and lie flat on the ground, preferably in a ditch. Do not remain in your car, since a tornado’s winds are capable of picking up a vehicle.

Conventional wisdom states that a tornado always has a visible funnel cloud, so you are safe if you do not see one approaching. This tornado myth is definitely not true! When the tornado first develops circulation, it may not show a funnel cloud. The low pressure and winds will still cause destruction. Also, a tornado can be hidden in the wall cloud of the thunderstorm – a cloud lowering attached to the rain-free base. Because the wall cloud indicates updraft, where circulation can form, tornado development in a wall cloud is not uncommon.

Finally, you may have heard that tornadoes cannot cross water or travel uphill. Tornadoes are able to move both up and down hills, so a building on a hill is not any safer than one below. Similarly, a lake or river is no protection, since tornadoes can pass over water, becoming waterspouts, then return to land and continue to wreak havoc.

Remember, even if you do not live in Tornado Alley, severe storms can still form tornadoes in your area. Tornadoes have occurred in all 50 states of the United States and most countries of the world. Know the facts and be prepared!